Song Choi, Presenter: Nothing to Disclose

Yun-Hyeon Kim MD, Abstract Co-Author: Nothing to Disclose

Hyun-Ju Sun, Abstract Co-Author: Nothing to Disclose

Jae Hoon Lim, Abstract Co-Author: Nothing to Disclose

Jae-Kyu Kim MD, PhD, Abstract Co-Author: Nothing to Disclose

Jin-Gyoon Park MD, Abstract Co-Author: Nothing to Disclose

To compare image quality, image noise, and radiation exposure associated 64-channel multi-detector computed tomography (MDCT) examination of coronary artery performed with z-axis modulation technique of automatic tube current modulation and with manual selection of fixed tube current.

Sixty consecutive slim subjects (weight, 2 circular ROI in the aorta at the origin of the left coronary artery and left atrium. Radiation dose was assessed via CT dose index (CTDI) on dose report. Data were analyzed parametric and nonparametric statistical tests.

No significant differences were found on image quality acquired with automated z-axis modulation, compared with images acquired with fixed tube current technique (p<0.05). Image noise is slight higher with automated z-axis modulation (SD=29.69) than fixed tube current (SD=28.47) but there was no statistic significance. The mean CTDI could be reduced from 87.9mGy in fixed tube current technique to 76.49mGy in automated z-axis modulation.

Compared with manually selected fixed tube current, z-axis automatic tube current modulation resulted in reduced radiation dose and similar image noise without impairing image quality at coronary MDCT.

This research attributes to the reduction of radiation dose in coronary MDCT by using the automated z-axis modulation.

Choi, S, Kim, Y, Sun, H, Lim, J, Kim, J, Park, J, Comparison of Z-Axis Automatic Tube Current Modulation Technique with Fixed Tube Current CT Scanning of Coronary Artery Using 64-channel MDCT.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5006417.html